Chemists say that "like dissolves like," meaning that polar solvents tend to dissolve polar solutes, and non-polar solvents tend to dissolve non-polar solutes, while non-polar and polar substances are immiscible (do not mix). Have you ever climbed a tree and gotten pitch on you and then found that getting it off was impossible? Have you tried to wash sticker residue off with water? Have you ever gotten grease on you and found that it was hard to get rid of? Why do we use nail polish remover to get rid of nail polish? Why won't water work? Knowing that "like dissolves like," it is possible to determine whether substances are polar or non-polar. Having this information makes the decision about what solvent to use for clean-ups much more effective.
Mix small portions of the items to be tested in water and than in oil to determine if they are polar or non-polar
| Items to be tested | In Water (Polar Solvent) | In Oil (Non-polar Solvent) | Polar or Non-polar? |
| Paraffin (candle wax, CnH2n+2) | |||
| Table Salt | |||
| Mineral Oil | |||
| Isopropyl Alcohol | |||
| "Lite Salt" KCl | |||
| Baking Soda NaHCO3 | |||
| latex-based paint | |||
| oil-based paint | |||
| glycerol |